Lubricating composition



United States Patent Ofifice Patented Feb. 28, 1967 This invention relates to an improved lubricating composition and more particularly to a lubricant suitable for use in the presence of air at high and ambient temperatures.

The trend in design of modern aircraft has accentuated the need for lubricants which will lubricate anti-friction bearings operating at high rotational speeds and high temperatures. Considerable progress has been made in recent years in producing improved aircraft lubricants. For example, a number of lubricants are now available for lubricating bearings operating at 10,000 to 20,000 revolutions per minute at temperatures up to about 400 F. However, great difiiculty has been encountered in producing a lubricant which will effectively lubricate bearings operating at speeds up to 20,000 revolutions per minute and at temperatures up to about 600 F. for prolonged periods of time.

In order to produce a lubricant, whether a liquid or a composition having the consistency of a grease, which will effectively lubricate bearings operating at temperatures up to 600 F., it is necessary to employ as the fluid component a material which is highly resistant to thermal degradation in the presence of air at temperatures up to 600 F. In addition, the fluid component must have the ability to lubricate and remain fluid both at high and ambient temperatures in the presence of air over a prolonged period of time without excessive volatilization, gumming or coking. If a composition having the consistency of a grease is prepared, the thickening agent employed in conjunction with the fluid must remain solid and also be resistant to thermal degradation at temperatures up to 600 F.

While some mineral oils especially hydrotreated mineral oils are sufliciently stable to provide adequate lubrication when used under moderately elevated temperatures, the volatility of mineral oils is such that they do not give ade quate lubrication at temperatures in the order of 600 F. Synthetic oils are more resistant to thermal degradation than mineral oils. Synthetic oils, particularly the olyorgano siloxanes known as the silicone oils in addition to being more resistant to thermal degradation than mineral oils also have high viscosity indices making their use at high and ambient temperatures especially desirable. Notwithstanding these desirable characteristics, the synthetic oils also have a tendency to volatilize and to solidify when heated at 600 F. in the presence of air over prolonged periods.

We have found that the tendency of a synthetic oil to volatilize and to solidify when heated at- 600 F. in the presence of air can be decreased by incorporating in said oil a small amount of a siloxanylferrocene. We have found further that when a siloxanylferrocene is incorporated in a polyorgano siloxane or a polyaryl ether together with an oil thickening proportion of a 1,3,5-triazine compound melting above about 600 F. (315 C.), a lubricating composition is obtained having an improved performance life. While we do not wish to be limited to any theory With respect to the reason for obtaining a thickened lubricating composition having an improved performance life, we believe that this improvement results at least in part from improving the volatilization and solidification tendencies of the fluid component. It is known, for example, that many of the properties possessed by a lubricating oil are imparted to the ultimate lubricating composition of which the lubricating oil is one of the constituents.

The siloxanylferrocenes which are employed according -to the invention can be either symmetrical or unsymmetrical siloxanylferrocenes. The symmetrical siloxanylferrocenes are represented by the general formula where R is hydrogen or a methyl radical, R and R are methyl or phenyl radicals, and n is an integer of 0 to 2. Specific examples of the symmetrical siloxanylferrocenes are Specific examples of the unsymmetrical siloxanylferrocenes are tris[ 1-phenyldimethylsilylferrocenyl) dimethylsiloxyl] methylsilane I l, l-bis 3-( 1 -phenyldirnethylsilylferrocenyl) -1, 1,3 ,3-

tetramethyldisiloxanyl] -ferrocene 1-trimethylsilyl-1-(3-phenyl-l,1,3,3-tetramethyldisiloxanyl) -ferrocene 1,5 -bis 1 '-trimethylsilylferrocenyl) 1, 1 ,3,3,5 ,5 -hexamethyltrisiloxane 1,3-bis[1-(3-phenyltetramethyldisiloxanyl)-ferrocenyl]- tetramethyldisiloxane l-phenyldimethylsilyl-l (3 -phenyll, 1,3 ,3-tetramethyldisiloxanyl) -ferrocene 1,5 -bis 1 '-phenyldimethylsilyl-l-ferrocenyl) -1, 1 ,3,3,5 ,5

hexamethyltrisiloxane The siloxanylferrocenes are known compounds and are available commercially so that neither the compounds per se nor their method of preparation constitutes any portion of the invention.

The symmetrical siloxanylferrocenes can be prepared by the method described in US. Patent No. 3,010,982 which issued on November 28, 1961 to Robert L. Schaaf, Carl T. Lenk and Harold Rosenberg. According to the disclosure in the patent, l,l-bis(S-phenylhexamethyltrisiloxanyl)ferrocene is prepared by a sequence of steps comprising (a) reacting l,3-dichlorotetramethy1disiloxane with cyclopentadienyllithium to produce l-cyclopentadienyl-3-chlorotetramethyldisiloxane; (b) reacting the 1- cyclopentadienyl-3-chlorotetramethyldisiloxane thus obtained with sodium phenyldimethylsilanolate to produce 1 cyclopentadienyl 5 phenylhexamethyltrisiloxane; and (c) reacting the l-cyclopentadienyl-S-phenylhexamethyltrisiloxane thus obtained with n-butyllithium and ferrous chloride to produce 1,1'-bis(S-phenylhexamethyltrisiloxanyl ferrocene.

The unsymmetrical siloxanylferrocenes can be prepared by the method described in US. Patent No. 3,036,105 which issued on May 22, 1962 to Robert L. Schaaf. According to the disclosure in the patent, tris[(l-phenyldimethylsilylferrocenyl)dimethylsiloxy]-methylsilane is obtained by a sequence of steps comprising (a) reacting nbutyllithium with cyclopentadiene to produce cyclopentadienyllithium; (b) reacting the cyclopentadienyllithium thus obtained with dimethyldichlorosilane to produce cyclopentadienyldimethylchlorosilane; (c) reacting the cyclopentadienyldimethylchlorosilane thus obtained with ethanol to obtain cyclopentadienyldimethylethoxysilane; (d) reacting the cyclopentadienyldimethylethoxysilane thus obtained with ferrous chloride in the presence of isopropylmagnesium chloride to produce 1,l-bis(dimethylethoxysilyl)ferrocene; (e) contacting the 1,1'-bis (dimethylethoxysilyl)ferrocene thus obtained with hydrochloric acid to produce 1,3-(l,1'-ferrocenylene)-tetramethyldisiloxane; (f) reacting the 1,3-(1,l'-ferrocenylene)-tetramethyldisiloxane thus obtained with phenyllithium and methyltrichlorosilane to produce (f1) a fraction comprising 1,3-(l,1'-ferrocenylene)-tetramethyldisiloxane and (2) a fraction comprising tris[(l-phenyldimethylsilylferrocenyl)dimethylsiloxy] methylsilane.

The amount of the siloxanylferrocene which we use may vary depending upon the particular lubricating base employed and upon the characteristics desired in the ultimate composition. 'In improving a synthetic oil, a sufficient amount of the siloxanylferrocene is used to decrease the normal tendency of the oil to volatilize and solidify. In general, the amount of the siloxanylferrocene required to improve the volatilization and solidification characteristics of the oil is about 0.01 to about 1 percent by weight of the oil. For optimum improvement of the oil, the siloxanylferrocene is employed in amounts of about 0.1 to about 0.3 percent by weight. In improving a composition having the consistency of a grease, a suflicient amount of the siloxanylferrocene is used to improve the performance life of the composition. In general, the amount of siloxanylferrocene required to improve the performance life of a composition having the consistency of a grease is greater than the minimum amount required to improve the thermal stability of the lubricating oil base used in preparing the thickened lubricant. Thus, the amount of siloxanylferrocene employed to improve the performance life of a composition having the consistency of a grease is about 0.2. to about 2 percent by weight of the total thickened lubricating composition.

The synthetic lubricating oil which is improved according to the invention is selected from the group consisting of the polyorgano siloxanes and polyaryl ethers. The polyorgano siloxanes are known commercially as silicones and are made up of silicon and oxygen atoms wherein the silicon atoms may be substituted with alkyl, aryl, alkaryl, aralkyl and cycloalkyl radicals. Exemplary of such compounds are the dimethyl silicone polymers, diethyl silicone polymers, ethylphenyl silicone polymers and methylphenyl silicone polymers. We also intend to include the halogenated silicones such as the fluorosilicones. We have obtained especially good results with polyorgano siloxanes having a high phenyl content and diphenylmethylsilyl end groups as well as with polyorgano siloxanes having a low phenyl content and trimethylsilyl end groups. Polyorgano siloxanes having a high phenyl content and diphenylmethylsilyl end groups can be obtained by hydrolyzing and polymerizing a mixture of diphenylmethylchlorosilane, dimethyldichlorosilane and diphenyldichlorosilane preferably in a mole ratio of 1: 1:1, respectively, according to procedures known to those familiar with the art. Polyorgano siloxanes having a lower phenyl content and trimethylsilyl end groups are similarly prepared by hydrolyzing and polymerizing a mixture of trimethylchlorosilane, dimethyldichlorosilane and phenylmethyldichlorosilane in a mole ratio of 1:325, respectively. While the polyorgano siloxanes are generally a mixture of polymers, general formulae representing the polymer mitxure by ideal molecules for the high and lower phenyl content polymers are as follows:

where x and y can be from 1 to 10 or more. Ideal molecules of each of the above general polyorgano siloxanes are as follows and ( 3)3 a)2 ]s[( e 5) a ]10 3)3 Molecular weight=1946 Exemplary of the polyaryl ethers which are improved according to the invention are the polyphenyl ethers, i.e., (phenyl)ether, m-bis(m-phenoxyphenoxy)benzene and m-bis(m-phenoxyphenoxy)phenyl ether.

The 1,3,5-triazine compounds which are employed as thickening agents according to the invention are limited to those compounds melting above about 600 F. (315 (1.). Exemplary of such compounds are 2,4-diamino-1,3, 5-triazine; 2,4-diamino-6-hydroxy-1,3,5-triazine (ammeline); 2,4-dihydroxy-6-amino-1,3,5-triazine (l-am melide); and 2,4-dihydroxy-6-pyridyl-1,3,5-triazine. While compounds melting below 315 C. can be used to produce grease compositions for use at temperatures below 600 R, such compounds are not satisfactory thickening agents for grease compositions used to lubricate bearings operating at high rotational speeds at temperatures in the order of 600 F. and higher for prolonged periods of time.

The 1,3,5-triazine compounds can be prepared according to known chemical procedures. Neither the compounds per se nor their preparation constitutes any portion of the invention. For example, 2,4-dihydroxy-6- pyridyl-1,3,5-triazine can be prepared by stirring for thirty minutes at room temperature a mixture of cyanuric chloride (18.5 gm., 0.1 mole), pyridine ml.) and water (500 ml.). The reaction mass is then filtered and the filtrate is concentrated on a water bath to give a product comprising 2,4-dihydroxy-6-pyridyl-1,3,5-triazine having a melting point above about 400 C, (752 F.).

The amount of the 1,3,5-triazine compound which we use is an amount sufficient to thicken the synthetic lubricating oil to a grease consistency. The exact amount in terms of weight percent may vary over wide limits depending upon the particular oil with which the triazine compound is blended and upon the properties desired in the final lubricating composition. While the triazine compound may comprise as much as 45 percent by weight of the total composition, we prefer to use smaller amount, that is, in the order of about 20 to about 40 percent by weight. It should be understood, however, that, depending upon the consistency of the composition desired less than 20 percent or more than 45 percent of the triazine compounds may be employed. In general, however, the 1,3,5-t1'iazine compounds comprises about 20 to about 45 percent by weight of the total composition.

In compounding the compositions of the present invention, various mixing and blending procedures may be used. In preparing an improved synthetic lubricating oil, the siloxanylferrocene is thoroughly admixed with the oil at room temperature. In preparing a composition having the consistency of a grease, the synthetic lubricating oil, the siloxanylferrocene and the triazine compound together with conventional lubricant additives, if desired,

6 of evaporation. The mobility of the fluids at 600 F. and after cooling to 80 F. is also observed.

In the tests summarized in Table I, the lubricating oils employed were synthetic lubricating oils known as are mixed together at room temperature for a period of 5 DC-550 Fluid and QF-6-7024 Fluid each of which is about 10 to 30 minutes to form a slurry. During this marketed -by Dow-Corning Corporation. DC-SSO Fluid initial mixing period some thickening is evidenced. Some is considered to be a methylphenylsiloxane polymer wherelum-ps may be formed. The slurry thus formed is then in the end silicon atoms are substituted to a high desubjected to a conventional milling operation in a ball gree by methyl groups. DC-550 Fluid has as typical mill, a colloid mill, homogenizer or similar device used 10 characteristics a viscosity at 100 F. of 300 to 400 SUS, in compounding greases to given the desired degree of a viscosity-temperature coefiicient of 0.75, a freezing point dispersion. In the illustrative grease compositions of this of 54 F., a flash point of 600 F. and a specific gravity invention, the slurry was passed twice, by means of a 25 C./25 C. of 1.08. It is believed that the types of pump through a Premier Colloid Mill set at a stator-rotor side chains present and their approximate molar perolearance of 0.002 inch. Maximum thickening occurred centages (in brackets) in DC-550 Fluid are phenyl (35), on the second pass through the mill. methyl attached through silicon to methyl (40) and meth- The lubricating composition of this invention can conyl attached through silicon to pheny-l (25). An ideal tain conventional lubricant additives, if desired, to immolecule of a polyorgano siloxane having this analysis is prove other specific properties of the lubricant without as follows: departing from the scope of the invention. Thus, the lubricating composition can contain a filler, a corrosion (CH3)3S1O[(QHQZSIOJiE(C6H5)CH3S1O]1OS1(CH3)3 and rust inhibitor, an extreme pressure agent, an anti- IF- Fluld 15 'cPnsldered a methylphellyloxidant, a metal deactivator, a dye and the like. Whether slloXane P e Wherem the Silicon atoms are or not such additives are employed and the amounts there- Stunted to hlgh degree y p y g p 6 of depend to a large extent upon the severity of the cont y l l 912-64024 FImd has typical characditions to which the compositon is subjected and upon the vlscoslty at 0f about 930 to 1030 stability of the synthetic lubricating oil base in the first aviscoslty at of about a viscosity instance. When such conventional additives are used lndex of about 108 l 110 and 3 P P of to they are generally added in amounts between about 0.01 It 15 Peheved 'E the YP of Side Chains and 5 percent by weight based on the weight of the total Present 1 than approxlmte molar Percentages composition brackets) in QF6 "7024 Fluid are phenyl (65), methyl In those compositions having the consistency of 3 attached through s lllcon to methyl (25) and methyl atgrease, auxiliary thickening agents such as finely-divided tached through slhcon Phenyl ideal moleamorphous silica o (G df Cabot, Ina), cule of a polyorgano slloxane havlng this analysis is as bentonite-organic base compounds Bentones (National follows: Lead Co.) and esterified siliceous solids Estersils (E. I. CH (C I-1 SiO (cH D SiO du Pont de Nemours and Company) can also be em- 5)z ]2 6 5)2 3 ployed. When an auxiliary thickening agent is employed, it is added in amounts of about 0.5 to about 5 percent by weight.

TABLE I Composition, Percent By Weight A B C D E F G H Lubricating Oil:

150-550 Fluid- 100 99. 9 QF6-7024 Fluid--. 100 99. 99 99. 9 99. 7 99. 5 siloxanylferrocene,l,1-bis( henylhexamethyltrisiloxanyl) ferrocene 0. 1 0. 01 0. 1 0. 3 0. 5 100 Inspection:

Evaporation, percent after the following number of hours at 600 F.:

Solid at 400 F. alter heating at 400 F. for 144 hours.

In order to illustrate the improved cha-racteritsics of lubricating compositions of the invention, various synthetic lubricating oils were compared with the same base oils containing a siloxanylferrocene. The test used in making the comparisons comprises placing ten grams of the test lubricant into ml. beakers cut to a height of 1% inches. The beakers are covered with stainless steel lids containing one inch hole. The beakers are placed in an oven where they are heated at a temperature of 600 in the presence of air. The beakers are with- The improved characteristics of synthetic lubricating compositions containing a siloxanylferrocene is evidenced by the data in Table I showing that the siloxanylferrocene gives an increase in the time over which the lubricating composition remains fluid at 80 F. and at 600 F. The

improved stability obtained by adding the siloxanylferrocene to the polyor-gano siloxanes was indeed surprising inasmuch as the siloxanyferrocene alone when heated to 600 F. in the presence of air was solid within 24 hours with a 31 percent loss in weight. Even when heated to i drawn periodically and weighed to determine the extent only 400" F. in the presence of air,

the siloxanylferrocene 7 solidified within 144 hours with a 31 percent loss in weight.

When the above test was repeated using other polyorgano siloxanes and polyaryl ethe-rs as the synthetic lubricating oil, similar improvement was noted when 1,1'-bis- (-phenylhexamethyltrisiloxanyl)ferrocene was added to the oil. A summary of the data obtained for compositions reported in Table I and other compositions showing the number of test hours before solidfication occurs appears in Table II.

end cap holding a reservoir of about 10 grams of additional grease. The bearing assembly containing an eightball SA'E No. 204 ball bearing is mounted on a horizontal spindle and is subjected to a radial load of 5 pounds. The portion of the spindle upon which the test bearing assembly is located is encased in a thenmostatically controlled oven. By this means the temperature of the bearing can be maintained at a desired elevated temperature which in the tests reported hereinafter was 600 F. The spindle is driven by a constant belt-tension motor drive assembly,

TABLE II Hours to solidification l,l-bis(5pl1enyl after heating to 600 F. Lubricating Oil hexamethyltrisilwith examination oxanyl) ferrocene percent by weight At 80 F. At 600 F.

None 100 24 24 Polyorgano siloxane:

DC-550 Fluid 24 48 Do B 120 144 QF-fi-7024 Fluid #1 144 192 D0 192 264 Do 288 336 Do 288 336 D0 216 240 GE-ll4-1403 Fluid 144 108 Do b 336 456+ GE-128-381 Fluid b 120 216 Do 216 456 Do 96 120 D0 b 144 168 GE-189-81 Fluid 144 288 Do h 384 432+ GE18984 Fluid 168 360 D0 h 384 432+ Polyaryl ether:

(Phenyl)5 ehter 144 216 D0 2l6 204 a Silicone oil marketed by Dow-Corning Corporation. 11 Silicone oil marketed by General Electric Company.

The improved characteristics of synthetic lubricating compositions containing a siloxanylferrocene is evidenced by the data in Table II showing that even as little as 0.01 percent by weight of the siloxanylferrocene gives a marked increase in the time over which the lubricating compositions remain fluid at 80 F. and at 600 F. It will be noted that optimum improvement is obtained with about 0.1 to about 0.3 percent by weight of the siloxanylferrocene.

In order to illustrate the lubricating characteristics of grease compositions of the invention when used to lubricate bearings operating at 600 F. and at rotational speeds of 20,000 revolutions per minute, Pope spindles were used in a test procedure similar to that outlined by the Coordinating Research Council Tentative Draft (July, 1954), Research Technique for the Determination of Performance Characteristics of Lubricating Grease in Antifriction Bearings .at Elevated Temperatures, CRC Designation L-35. According to the CRC L test method, the test bearings are packed with 3.5 cc. (or equivalent weight) of grease. Because of the extremely short life of bearings packed with 3.5 cc. of grease, the present evaluations were made by packing the bearings completely full with about 6 to 8 grams of grease and using either a standard end cap with no additional grease or a special capable of giving spindle speeds of 20,000 revolutions per minute. The spindle is operated on a cycling schedule consisting of a series of periods, each period consisting of 20 hours running time and 4 hours shutdown time. The test continues until the lubricant fails. The lubricant is considered to have failed when any one of the following conditions occurs, (1) spindle input power increases to a value approximately 300 percent above the steady state condition at the test temperature; (2) an increase in temperature at the test bearing of 20 F. over the test temperature during any portion of a cycle; or (3) the test bearing locks or the drive belt slips at the start or during the test cycle.

The lubricating oils used in preparing the lubricating compositions shown in Table III were m-bisfirn-phenoxyphenoxy)phenyl ether and QF6-7024 Fluid as described more fully hereinabove.

In preparing the illustrative lubricating compositions, the oil, the am mel'ine and the siloxanylferrocene were mixed at room temperature for a period of 10 to 30 minutes. The slurry thus formed was passed twice through a Premier Colloid Mill set at a stator-rotor clearance of 0.002 inch. The approximate make-up and properties of the thickened lubricating compositions thus prepared are set forth in Table III.

TABLE III Composition, percent by weight Synthetic Lubricating Oil:

QF-67024 Fluid rn-Bis(m-phenoxyphenoxy)phenyl ether Ammeline I Results of two tests.

The long performance life of the compositions of the inventi-on (Compositions B and D) at a high rotational speed and a high temperature is self-evident from the above data. By comparing Composition B and D with Compositions A and C, respectively, it will be noted that the addition of l,1-bis(S phenylhexameth ltrisiloxanyl) ferrocene improves the performance life of the composition.

Other lubricating compositions within the scope of the invention are illustrated in Table IV. The Cab-O-Sil employed in some of the illustrative compositions is a finely-divided amorphous silica marketed by Godfrey L. Cabot, Inc. This silica is a subm'icroscopic particulate silica prepared in a hot gaseous environment (1100 C.) by the vapor-phase hydrolysis of a silicon compound. On a moisture-tree basis, this silica is 99.0 to 99.7 percent silicon dioxide which is practically free from contaminating metallic salts. Gravimetric analysis fail to detect the presence of any calcium or magnesium. The iron content has been found to be about 0.004 percent and volatile matter removed on ignition at 1000 C. amounts to less than 1 percent. Cab-O-Sil is an extremely fine silica with particles ranging in size from 0.0 to 0.020 micron.

TABLE IV of the lubricating oil, a siloxanylferrocene selected from the group consisting of symmetrical and unsymmetrical siloxanylferrocenes.

2. A lubricating composition consisting essentially of R CH Composition, Percent By Weight A Lubricating Oil, QF-fi-7024 A mmeline O ab-O-Sil Siloxanylt'errocene:

1,1b is (S-phenyltetramethyl disiloxanyl) ferrocene.

1,1-bis(7-phenyl0ctamethyltetrasiloxanyl) ferrocene.

1, 1-b is (pentamethyldisiloxanyl) ierrocene 1,1-bis(3-phenyltetramethyldisiloxanyl) dimethylierrocene 1,1-bis(5-pheny1hexamethyltrisiloxanyl)dimethyl ferrocene Tris[(1-pheny1dimethylsilylferrocenyl)dimethylsiloxy]-methylsihne 1,5-bis(1-phenyldimethylsilyl-l-ferroceny1)- l,1,3.3,5,5-hexamethyltrisi fl While our invention has been described with reference to various specific examples and embodiments it will be understood that the invention is not limited to such examples and embodiments and may be variously practiced Within the scope of the claims hereinafter made.

We claim:

1. A lubricating composition consisting essentially of a lubricating oil selected from the group consisting of the liquid polyorgano siloxanes and polyaryl ethers normally tending to volatilize and solidify when heated at 600 F. in the presence of air and a small amount, sufiicient to decrease the volatilization and solidification tendencies hexamethyltrisiloxanyl)ferrocene.

4. The lubricating composition of claim 3 wherein the siloxanylferrocene comprises about 0.01 to about 1 percent by weight of the total composition.

5. A lubricating composition consisting essentially of a liquid polyorgano siloxane and about 0.01 to about 1 percent by weight of 1,1-bis(5-phenylhexamethyltrisiloxanyl ferrocene.

6. A lubricating composition consisting essentially of a liquid polyorgano siloxane and about 0.01 to about 1 per-cent by weight of 1,1-bis(3-phenyltetramethyldisiloxany1)ferrocene.

7. A lubricating composition consisting essentially of a liquid polyorgano siloxane and about 0.01 to about 1 percent by Weight of 1,1'-bis(5-phenylhexamethyltrisiloxanyl) dimethylferrocene.

8. A lubricating composition consisting essentially of a liquid polyorgano siloxane and about 0.01 to about 1 percent by weight of 1,5-bis,1-phenyldimethylsilyl-l-ferrocenyl)-1,1,3,3,5,5-hexamethyltrisiloxane.

9. A lubricating composition consisting essentially of a liquid polyphenyl ether and about 0.01 to about 1 percent by weight of 1,1'-bis(5-phenylhexamethyltrisiloxanyl ferrocene.

10. A lubricating composition consisting essentially of a dispersion in a lubricating oil selected from the group consisting of the liquid polyorgano siloxanes and polyaryl ethers of a sufficient amount to thicken the lubricating oil to a grease consistency of a 1,3,5-triazine compound melting above about 315 C. and of a sutfiicient amount to improve the performance life of the composition of a siloxanylferrocene selected from the group consisting of symmetrical and unsymmetrical siloxylferrocenes.

11. The lubricating composition of claim wherein the 1,3,5-triazine compound comprises about 20 to about 45 percent by weight of the total composition and the siloxanylferrocene comprises about 0.2 to about 2 percent by weight of the total composition.

12. A lubricating composition consisting essentially of a dispersion in a liquid polyorgano siloxane of a sufficient amount of ammeline to thicken the polyorgano siloxane to a grease consistency and a small amount, sufficient to improve the performance life of the composition, of a symmetrical siloxanylferrocene represented by the formula where R is selected from the group consisting of hydrogen and a methyl radical, R and R are selected from the group consisting of methyl and phenyl radicals and n is an integer of O to 2.

13. The lubricating composition of claim 12 wherein the ammeline comprises about 20 to about 45 percent by weight of the total composition and the siloxanylferrocene comprises about 0.2 to about 2 percent by weight of the total composition.

14. A lubricating composition consisting essentially of a dispersion in a liquid polyorgano siloxane of a sufficient amount of ammeline to thicken the polyorgano siloxane to a grease consistency and about 0.2 to about 2 percent by weight of the total composition of 1.1'-'bis(5- phenylhexamethyltrisiloxanyl)ferrocene.

15. A lubricating composition consisting essentially of a dispersion in a liquid polyorgano siloxane of a sufficient amount of ammeline to thicken the polyorgano siloxane to a grease consistency, about 0.2 to about 2 percent by weight of 1,1-bis(5-phenylhexamethyltrisiloxanyl) ferrocene and about 0.5 to about 5 percent by weight of finely-divided silica.

16. A lubricating composition consisting essentially of a dispersion in a liquid polyphenyl ether of a sufficient amount of ammeline to thicken the polyphenyl ether to a grease consistency and about 0.2 to about 2 percent by Weight of the total composition of 1,1-bis(5-pheuylhexamethyltrisiloxanyl) ferrocene.

References Cited by the Examiner UNITED STATES PATENTS 2,831,880 4/1958 Benkeser 260439 3,010,982 11/1961 Schaaf et al. 260-439 3,036,105 5/1962 Schaaf 260439 DANIEL E. WYMAN, Primary Examiner.

I. VAUGHN, Assistant Examiner. 

1. A LUBRICATING COMPOSITION CONSISTING ESSENTIALLY OF A LUBRICATING OIL SELECTED FROM THE GROUP CONSISTING OF THE LIQUID POLYORGANO SILOXANES AND POLYARYL ETHERS NORMALLY TENDING TO VOLATILIZE AND SOLIDIFY WHEN HEATED AT 600*F. IN THE PRESENCE OF AIR AND A SMALL AMOUNT, SUFFICIENT TO DECREASE THE VOLATILIZATION AND SOLIDIFICATION TENDENCIES OF THE LUBRICATING OIL, A SILOXANYLFERROCENE SELECTED FROM THE GROUP CONSISTING OF SYMMETRICAL AND UNSYMMETRICAL SILOXANYLFERROCENES.
 15. A LUBRICATING COMPOSITION CONSISTING ESSENTIALLY OF A DISPERSION IN A LIQUID POLYORGANO SILOXANE OF A SUFFICIENT AMOUNT OF AMMELINE TO THICKEN THE POLYORGANO SILOXANE TO A GREASE CONSISTENCY, ABOUT 0.2 TO ABOUT 2 PERCENT BY WEIGHT OF 1,1''-BIS(5-PHENYLHEXAMETHYLTRISILOXANYL) FERROCENE AND ABOUT 0.5 TO ABOUT 5 PERCENT BY WEIGHT OF FINELY-DIVIDED SILICA. 